Boardgamegeek has posts from some players who have played. It seems to be extremely adventure-based and from what I gathered,the adventure outcome determines whether the kingdom is saved or lost. I feel that is different from Defenders of the Realm…at least different enough for me.
The information is still not clear…but I like what I've read so far.
It reminds me of an old game I played called "Red Storm Rising" where individual scenarios dictated the outcome of the whole war.